Arenoa System

Arenoa A is a single K-type main-sequence star serving as the gravitational and energetic anchor of the Arenoa system. Its warm orange coloration and moderate luminosity place it below solar output, resulting in a system where inner planets experience intense irradiation while outer bodies remain cold and slow-evolving. The star’s emission spectrum is stable, with minimal flare activity, allowing long-term orbital coherence across the system.

Spectroscopic observations indicate a slightly elevated metal content, consistent with the formation of massive gas giants in the outer regions. Residual dust within the system plane suggests the Arenoa system formed from a dense protoplanetary disk, fragments of which persist today as both the asteroid belt and circumplanetary material around the outer planets.

The Arenoa asteroid belt is an inner circumstellar debris field located closer to Arenoa A than the rocky planet Arenoa B-1. Unlike typical rocky belts, it is composed predominantly of icy bodies, including water ice, frozen volatiles, and dust-coated ice fragments. The belt forms a faint, diffuse ring around the star, detectable primarily through infrared excess and forward-scattered light.

Its unusual inner position suggests formation during an early phase of the system when the stellar output was significantly lower, allowing volatile compounds to condense closer to the star. As Arenoa A matured and increased in luminosity, the belt remained gravitationally stable but dynamically eroded, with continuous sublimation and collisions replenishing fine particulate ice within the system.

Arenoa B-1 is a dense terrestrial planet occupying the innermost stable orbit around Arenoa A. Its proximity to the star results in extreme surface temperatures and intense stellar irradiation, preventing the long-term retention of a substantial atmosphere. The planet’s surface is believed to be dominated by exposed rock and metallic regions shaped by prolonged thermal stress.

Tidal interactions with the parent star likely contribute to strong tectonic activity and partial tidal locking. Observational data suggest significant day–night temperature gradients, with localized molten regions on the dayside and rapid radiative cooling on the nightside, making Arenoa B-1 an inhospitable but geologically dynamic world.

Arenoa B-2 is a massive gas giant distinguished by its pale sandy-yellow atmosphere and an exceptionally expansive ring system extending to nearly twenty times the planet’s diameter. The atmosphere is composed primarily of hydrogen and helium, with high-altitude haze layers of silicate and hydrocarbon aerosols responsible for its muted coloration.

The ring system dominates the planet’s visual and physical presence, forming a thin but vast disk of soot, dust, and fragmented moon material. Multiple density gaps and faint spiral structures within the rings suggest the influence of embedded shepherd moons, as well as the remnants of past tidal disruption events.

Arenoa B-3 is the outermost gas giant in the Arenoa system, orbiting at a great distance from the parent star where temperatures remain consistently low. Its atmosphere appears dark and muted, composed of deep cloud layers with minimal visible banding due to weak stellar illumination and slow atmospheric circulation.

Faint observational signatures suggest the presence of a tenuous ring system, likely composed of fine ice particles and debris from minor moons. These rings are narrow and low-density, contributing little to the planet’s brightness and remaining difficult to resolve except in high-contrast imaging.